The present disclosure relate to a display and input device having a display section and a touch screen section and also relates to an image forming apparatus that includes such a display and input device.
Electric and electronic devices may be equipped with a display panel. A typical display panel incorporates a touch screen used to input settings or perform operations on the device. The display panel displays images of keys, buttons, tabs, and so on used for various settings. When a user performs a touch operation, the touch screen detects the touch position and compares the coordinates specifying the touch position with the display coordinates of the images of keys, buttons, tabs, and so on to determine an image that is operated. In this way, the display panel receives inputs made by the user for various settings. Unfortunately, the coordinates of a position actually touched on a screen by a user may not precisely correspond to the position (coordinates) detected as the touch position by the device (system). The deviation between the actual touch position (coordinates) by the user and the detected coordinates (position) by the device (system) may result in that the key touched by the user is not correctly determined as the operated key (In the following description, such a deviation may be referred to as a “deviation between the actual touch position coordinates and the detected touch position coordinates”). One known example discloses a technique for calibrating the deviation between the actual touch position coordinates and the detected touch position coordinates.
More specifically, the example discloses a touch panel device that includes a display section and a touch screen layered on the display section. The touch panel device has a function of converting values detected for a touch position on the touch screen into coordinates specifying the touch position on the display section and also a has calibration function. With the calibration function, the touch panel device first acquires a translation calibration value between the coordinates of a first reference point displayed on the display section and the coordinates detected for a touch operation on the first reference point. The touch panel device additionally acquires a rotation calibration value between the coordinates of a second reference point displayed on the display section and the coordinates detected for a touch operation on the second reference point, with the first reference point taken as the center of rotation. The touch panel device then calibrates the coordinates detected for a touch position through calibration based on the rotation calibration value in addition to the translation calibration value. This configuration enables the calibration to correct the deviation of detection resulting from that the touch screen is twisted relative to a specific reference point on the display device.